Learn Polish: Podczas sesji dzielimy się naszymi emocjami jeden z drugim. - During the session, we share our emotions with one another.

The Polish verb dzielić się means to share. You share something using the instrumental case (here, naszymi emocjami), but you share it with someone using the preposition z plus the instrumental case. The reciprocal phrase literally means 'one [shares] with the second', so it inserts the preposition z exactly where it would go if you were naming a specific person.

Could we just use nawzajem at the end of this sentence instead?

Yes, dzielimy się naszymi emocjami nawzajem is grammatically correct and means the same thing. However, using the explicit reciprocal jeden z drugim is slightly more expressive. It paints a stronger picture of individuals interacting directly with each other, rather than just a general mutual action.

If this session was exclusively for women, would the phrase jeden z drugim change?

Yes! The phrase jeden drugi declines for gender to match the people involved. If the group is entirely female, you must use the feminine forms: jedna z drugą. Because the sentence as written uses the masculine/mixed form jeden z drugim, we know the group contains at least one man.

Since 'we share' implies multiple people, why use the singular jeden z drugim instead of the plural jedni z drugimi?